The general objective of this invention is to improve the diversity and utility, as well as the convenience of use, safety and simplicity of operation of a portable power tool table of the general type shown in U.S. Pat. No. 4,320,678.
More particularly, it is one of the objectives of the invention to enable the use of a sabre saw in various cutting modes, including compound angle cutting of workpieces without the possibility of injuring or severing the fingers, as can occur in some cases where the base of the sabre saw is supported and guided at a fixed height above the table and workpiece.
Another object is to provide a table and adjustable guide rail structure which permits use of a sabre saw in various ways so that all of its operational capabilities are taken advantage of, namely, straight and angle cutting with the saw blade in a vertical plane, compound angle cutting with the blade tilted relative to the vertical, cutting of cove molding in cooperation with a protractor on the table, and rip sawing across the axis of the guide rail means.
The essence of the invention resides in the provision of two distinct modes of support or use of the adjustable guide rail assembly relative to the underlying table. In one mode of use, the guide rail assembly is held at a fixed elevation above the table and above any workpiece resting on the table. In this mode, the guide rail assembly can support a portable circular saw or router and may also support a sabre saw for ripping lumber with the saw blade disposed in a plane across the longitudinal axis of the guide rail assembly. In another mode of operation, the guide rail assembly is floatingly supported while being restrained against lateral or longitudinal displacement. It rests on the top face of any workpiece on the table within the thickness range which the device can accommodate. In this second mode of use, the guide rail assembly supports and guides a sabre saw and facilitates the full range of utility of such saw including the making of compound angle cuts and the cutting of cove molding with precision and smoothness, in cooperation with a protractor attachment provided on the table. A simplified version of the table provides only this second mode of use.
In the two modes of use of the adjustable guide rail assembly, mounting plates for the assembly at its opposite ends have keyhole slots whose enlarged ends slidably engage locator posts rising from the table to facilitate the floating mode of use. When used at a fixed height above the table, the guide rail assembly mounting plates rest on the tops of the locator posts with the narrow ends of the keyhole slots shifted to engage the shanks of clamping or locking screws.
One end of the guide rail assembly can be raised and lowered and locked in a selected adjusted position to level the guide rails with precision so as to further enhance smooth chatter-free operation of a sabre saw.
Other features and advantages of the invention will become apparent during the course of the following detailed description.